Characterisation of tunable multiple section semiconductor lasers

The drive towards higher bandwidth optical fibre networks using multiple wavelength systems is increasing the importance of wavelength tunable semiconductor laser transmitters. Thermal tuning and the use of discrete fixed wavelength lasers have been used extensively but for full flexibility and rapid response, electronic methods of tuning are essential; electronic tuning ranges of over 100 nm have been demonstrated using sampled grating based structures. Concurrent modelling and measurements are being used to fully characterise these complex structures. Because of the complexity of these lasers, a computer controlled test facility which will fully characterise the wavelength coverage of lasers with up to four contacts, has been developed. A variety of existing and newly developed tunable lasers have been tested